> For my project I think I prefer the first sulotion, can I have your example
> code please.
Sorry to take a while getting back to you - I had a lo-fi weekend.
Ok, the 'search engine' has three parts to it
1. A domain - basically, a big list of nested lists of things to search
2. A list processor - which goes through the domain list
3. Search methods - which get applied to the things in the domain list.
Once you have a list of the castmembers you want to search, you need to go
through the list and do a search on each item in the list. The simplest and
fastest way of processing a list is recursively like this -
on findInList pList
pListMX = pList.count
repeat with i = 1 to pListMX
thisEntry = pList[i]
if listP(thisEntry) then findInList(thisEntry)
else doSearchOn(thisEntry)
end repeat
end
This is very fast. However, if its a really big list, then you might have
memory problems. More importantly, a big repeat loop like this, although
incredibly quick, will lock up the processor while its working. The
alternative way is to step through the list on stepFrame or similar.
This 'threaded' approach is much slower, but doesn't lock out other
processes. It works quickly if the framerate is high. I've pasted in a
"ListProcessor" parent script below which shows a way of processing big
nested lists. Its been setup to be used as an ancestor or daemon for another
object. In otherwords, it simpley works out which item in the list its up
to, the calls the specified object with the method that was passed to it as
a parameter when the search was initiated.
Its also desgined to handler lists of nested lists such as
[["A", "B"], ["C", "D", "E"],["F"], "G", ["H", "I"]]
You could simplify it considerably if you are only processing flat lists.
Luke
------------------- ListProcessor Script ----------------------
property myRootList, myProcessMsg, myFinishedMsg, myServicedObj
property threaded_CurrentIndex, threaded_CurrentTrail, thread_Status
----// INIT & DESTROY
on new me
myRootList = []
myProcessMsg = VOID
myFinishedMsg = VOID
myServicedObj = VOID
---
threaded_CurrentIndex = 0
threaded_CurrentTrail = [] -- trail of branching points
thread_Status = #finished
(the actorList).append(me)
return me
end
on mDestroy me
(the actorList).deleteOne(me)
end
----// EVENT
on stepFrame me
me.mRunThread()
end
----// PUBLIC
on mProcessList me, pList, pProcessMsg, pFinishMsg, pObj
-- The object using the threadMgr must specify
-- pList: the list to be processed
-- pProcessMsg: the method to be called to process the list items
-- pFinishMsg: the method to the called when the thread finishes
-- pObj: the object that handles these calls
myRootList = pList
myProcessMsg = pProcessMsg
myFinishedMsg = pFinishMsg
myServicedObj = pObj
---
if myRootList.count = 0 then
if symbolP(myFinishedMsg) then call(myFinishedMsg, myServicedObj)
--
else
threaded_CurrentIndex = 0
threaded_CurrentTrail = [] -- trail of branching points
thread_Status = #running
end if
end
----// PRIVATE
on mRunThread me
currentSearchList = myRootList
mx = threaded_CurrentTrail.count
if mx > 0 then
repeat with i = 1 to mx
BranchPoint = threaded_CurrentTrail[i]
currentSearchList = currentSearchList[BranchPoint]
end repeat
end if
threaded_CurrentIndex = threaded_CurrentIndex + 1
if threaded_CurrentIndex > currentSearchList.count then
-- finished with current sub list
if threaded_CurrentTrail.count > 0 then
-- close current branch
threaded_CurrentIndex =
threaded_CurrentTrail[threaded_CurrentTrail.count]
threaded_CurrentTrail.deleteAt(threaded_CurrentTrail.count)
else
-- finish
if thread_Status <> #finished then
thread_Status = #finished
if symbolP(myFinishedMsg) then call(myFinishedMsg, myServicedObj)
end if
end if
else
-- still processing current list
thisEntry = currentSearchList[threaded_CurrentIndex]
if listP(thisEntry) then
-- open new branch
threaded_CurrentTrail.append(threaded_CurrentIndex)
threaded_CurrentIndex = 0
else
-- found something to process
call(myProcessMsg, myServicedObj, thisEntry)
end if
end if
end
-------------------- Example Script which uses the ListProcessor ------
property myListProcessor
on new me
myListProcessor = script("ListProcessor").new()
return me
end
on mTestListProcessor me
aList = [["A", "B"], ["C", "D", "E"],["F"], "G", ["H", "I"]]
myListProcessor.mProcessList(aList, #mProcessMethod, #mFinishMethod, me)
end
on mProcessMethod me, pListItem
put "Found " & pListItem
end
on mFinishMethod me
put "Finished!! "
end
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